Folded-box blanks made out of cardboard and glued to form sleeves are unfolded with such a device by applying a compressing pressure onto opposite edges of the folded-box sleeves. When unfolding a flat folded-box sleeve, its cross section is changed into a rectangle. The bottom-side face of the folded box is subsequently glued and closed off, the folded box is filled, for example, with a tubular bag, and finally the top-side face is glued and closed off.
Devices are known for unfolding the folded box fully through mechanical pressure along a compressing section, namely until right inner angles exist at all four edges of the folded-box sleeve. Only then is the folded-box sleeve moved on or further processed. The full unfolding, however, takes relatively long. This time requirement is disadvantageous for relatively quick packaging operations.
The purpose of the invention is to avoid a relatively long time for the full mechanical unfolding of a folded-box sleeve and yet achieve fully unfolded folded-box sleeves.